Container head with drip-less seal and method for producing the same

ABSTRACT

The present invention is a container head containing a resilient annular sealing ring projecting from the surface plane of the shoulder of the container head. When the cap is seated on the container head, the resilient annular sealing ring forms a secondary fluid-tight seal between the container head and cap.

INTRODUCTION

This application claims the benefit of priority from U.S. provisionalapplication Ser. No. 60/746,197, filed May 2, 2006, which is hereinincorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

Containers such as plastic tubes and bottles are used to dispense anumber of different products from body creams, lotions, shampoos andconditioners, to pharmaceutical ointments and creams. In general, theconsumer desires a clean, easy to dispense, package and product. Mostconventional tube and bottle packages have threaded or snap-on caps thatfit to a molded threaded or snap-on head. These designs all leave asmall space between the cap and the container head which can get filledwith water or dirt. Since many containers are being designed to stand onthe cap and many of these products are used in the shower, water fillsthe cap and pours out during use. This is especially unsatisfactory tothe user when the water is cold or soapy and has been standing in thecap for a period of time.

Caps have been designed to contain a flange on the outer lip of the capso that when contacted with the head of the tube a seal is created(Zeller Plastik, a Crown Cork & Seal company). See, e.g., U.S. Pat. No.6,578,744. The drawbacks to this design are that it does not accommodatea wide variety of caps or tube designs and because the flange is rigid,the flange cuts into the tube head in order to create a seal. Thiscutting action can create plastic stings and dust on the tube head,which are considered contaminants.

U.S. patent application Ser. No. 10/498,241 also discloses a beveragebottle with a flange on the outside diameter of the cap, whichcorresponds to the outside diameter of the bottle edge.

U.S. Pat. No. 6,637,966 teaches a cap and a resilient sealing ring thatseals between a shoulder of the container and an annular lip of the capto provide an ectoseal. However, the sealing ring is neither integralwith the cap nor the container.

SUMMARY OF THE INVENTION

The present invention is a container head with a drip-less seal. Thecontainer head of the invention has integrated into the shoulder thereofan annular sealing ring, which forms a fluid-tight seal with theinterior surface of a container cap. Containers and methods forproducing the container of head of the invention are also provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a molded container head 10 with annularsealing ring 12 extending beyond the plane of the container shoulder 14and contacting the inner surface of cap 20.

FIG. 2 is a sectional view of a molded container head 10 with annularsealing ring 12 extending beyond the plane of the container shoulder 14and contacting chamfer 22 at the leading edge of cap 20.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is a container head with a resilient sealingmember and method for producing the same. The improved container headprovides a fluid-tight seal which prevents external water or otherforeign materials from accumulating under the cap, i.e., in the spacebetween the cap and the container head. The resilient sealing member isan annular sealing ring molded with the container head which contactsthe cap to form a secondary seal at the inner surface of the cap wall.Advantageously, the instant container head can be used in combinationwith any type of cap including, threaded or snap-on caps.

By way of illustration, FIG. 1 depicts the instant molded container head10 with a resilient annular sealing ring 12 contiguously molded intoshoulder 14 of container head 10. As used herein, contiguously molded isintended to mean that the molded container head 10 and resilient annularsealing ring 12 are molded from a single piece of material. Containerhead 10 is intended to encompass the narrowing portion of a containerthrough which fluid from the container body is dispensed. As such,container head 10 encompasses shoulder 14, collar or neck 16, andopening (not shown) located at the top of the container for dispensingthe product. Alternatively stated, container head 10 is the portion ofthe container located above the body 18 of the container.

According to the present invention, annular sealing ring 12 projects orextends away from the surface plane of the shoulder 14 so that when thelid or cap 20 is seated on the tube head 10, annular sealing ring 12contacts the inner surface or wall of cap 20 (FIG. 1) or chamfer 22 atthe leading edge of cap 20 (FIG. 2). In particular embodiments, annularsealing ring 12 is integrated (i.e., contiguous) with the shoulder 14 ofthe container. As such, annular sealing ring 12 and shoulder 14 areproduced from a single piece of material to create a unitary one-piececonstruction. The purpose of annular sealing ring 12 is to deformagainst cap 20 thereby forming a seal between the contacting surface ofthe container head 10 and the cap 20. In particular embodiments, thecontainer is a squeeze type tubular container that is made of a softplastic that is desirably softer than the material from which the cap 20is fabricated. As such, annular sealing ring 12 is resilient or flexibleand when pressed against the contacting surface of cap 20, annularsealing ring 12 will deflect to some degree, forming in effect asecondary fluid-tight or drip-less seal between the cap 20 and thecontainer head 10.

As used in the context of the present invention, a container is intendedto include squeeze tubes, squeeze bags, and squeezable bottles used forpackaging and dispensing non-solid products of the type which arecapable of flowing. Non-solid products include fluid or fluidizedmaterials, including liquids, pastes, powders, and the like, which arecollectively and generically referred to herein as fluids. Squeeze tubesor bags and squeezable bottles are flexible packages made from plasticmaterial (e.g., low or high density polyethylene, polypropylene,polyethylene terephthalate, polyvinyl chloride, softouch, dual layer, orcoextruded plastics), elastic material (e.g., silicone, thermoplasticelastomer, natural rubber, or synthetic rubber such as isoprene), orcombinations thereof with one open end and one closed end. In particularembodiments, the container is a squeeze tube or bag formed by sealing afilled tube at one end resulting in a package with a cylindrical, openend and a flattened, closed end (e.g., a toothpaste tube).

In accordance with the present invention, the annular sealing ring ismolded into the container head during the process of producing thecontainer head. Thus, the one-piece construction of the container headis produced by selecting a suitable material and compression molding,injection molding, or bi-injection molding (e.g., when employing acombination of materials) a container head with a thin resilient annularsealing ring extending away from the surface plane of the shoulder. Aswill be appreciated by the one of skill in the art, the material for thecontainer head can be any moldable material selected for producing theinstant container head and can be dependent upon several factorsincluding the flow properties of the fluid being dispensed and whetherthe container head is contiguous with the body of the container, anintegral part of the container cap or lid, or produced as a separatecomponent and welded to the container body. Desirably, the materialselected for producing the container head is resilient and flexible,retaining its physical and/or chemical characteristics in response toambient changes such as temperature fluctuations, repeated use, orexposure to active ingredients in the product. However, because thecontainer material is composed of the same material as the annularsealing ring, it may be necessary to respectively select a more rigidcontainer cap material or container body material suitable to stabilizethe flexible material required of the annular sealing ring.Advantageously, the flexible nature of the annular sealing ring is animprovement over seals integrated into the cap or lid as a bettersecondary seal is created with no cutting of the cap or tube head, andtherefore no generation of plastic strings or dust during capapplication.

The container head of the invention finds application in the packagingand dispensing of a variety of consumable or purchased goods or productsincluding consumable products such as personal care products (e.g.,soaps, shampoos, make-up, insect repellents, and the like); first aidproducts (e.g., ointments, sunscreens, and the like); cleaners (e.g.,detergents and cleaning solutions); paints; and foodstuffs (e.g.,yogurt, cheese-like products, jelly, oils, condiments, and the like).The instant invention is a significant improvement in the manufacture ofcontainers as it provides a secondary seal to the primary package sealprovided by the seal typically contained in the cap thread area. Onthreaded caps the primary seal ring is typically a V-seal ring whichcontacts the land at the top of the container head and seals the Vagainst the land as the cap is screwed or snapped onto the container. Insnap-on cap designs, the snap-in bead, which holds the cap in place,generally creates the primary seal. While the primary seal is designedto keep the product from leaking out of the container, the secondaryseal, provided by the present invention, is intended to keep foreignmatter from entering between the space between the cap and the containerhead. This secondary seal also provides another purpose in that it sealsthe container and prevents leakage if the primary seal fails. This isimportant when the cap is not properly closed thereby causing theproduct to leak past the primary seal. The secondary seal preventsleakage if the cap is not screwed back tightly on the tube.

1. A container head with a drip-less seal comprising a shoulder havingan annular sealing ring, wherein the annular sealing ring forms a fluidtight seal with the interior surface of a container cap.
 2. Thecontainer head of claim 1, further comprising a container body.
 3. Amethod for producing a container head with a drip-less seal comprisingmolding a container head material into a container head with an annularsealing ring integrated into the shoulder thereof thereby producing acontainer head with a drip-less seal.